Documentation: what should happen?

[philtomson]

I managed to build the kernel.img on my RPi and then copied it to a Raspian SD card (replacing the one that was in /boot/kernel.img). Then I plugged that SD card into the RPI and started it up. I saw the RPi bootup screen (for recovery mode press shift) and then that went blank and... nothing.

[mrvn]

On Sat, Jun 21, 2014 at 03:41:56PM -0700, Phil Tomson wrote:

I managed to build the kernel.img on my RPi and then copied it to a Raspian SD card (replacing the one that was in /boot/kernel.img). Then I plugged that SD card into the RPI and started it up. I saw the RPi bootup screen (for recovery mode press shift) and then that went blank and... nothing.

---

Reply to this email directly or view it on GitHub:
#3

Anything on the serial console?

MfG
Goswin

[philtomson]

Finally got around to trying out the serial console. This is what I'm seeing (It doesn't let me login) :
Uncompressing Linux... done, booting the kernel.
�
Welcome to the rescue system
recovery login:
Welcome to the rescue system
recovery login:

[mrvn]

On Wed, Jul 02, 2014 at 02:23:23PM -0700, Phil Tomson wrote:

Finally got around to trying out the serial console. This is what I'm seeing (It doesn't let me login) :
???
Welcome to the rescue system
recovery login:
Welcome to the rescue system
recovery login:

Then you aren't booting ocaml-rpi.

MfG
Goswin

[philtomson]

Ok, so here's what I did:

1. I ran your Makefile on the rPi to get the kernel.img
2. I duplicated a Raspian SD card with dd & then mounted the resulting microSD card.
3. Then I copied the kernel.img from (1) to the duplicate Raspian in the boot mount point replacing the one that was there.

I notice that there is a kernel_emergency.img in that boot folder, so apparently that's what's trying to boot - possibly because it doesn't like the kernel.img that was created from ocaml-rpi?

Also, I just grepped for "Hello World" in the kernel.img that was generated and it does find the string in there.

[mrvn]

On Fri, Jul 04, 2014 at 08:48:24AM -0700, Phil Tomson wrote:

Ok, so here's what I did:

1. I ran your Makefile on the rPi to get the kernel.img
2. I duplicated a Raspian SD card with dd & then mounted the resulting microSD card.
3. Then I copied the kernel.img from (1) to the duplicate Raspian in the boot mount point replacing the one that was there.

I notice that there is a kernel_emergency.img in that boot folder, so apparently that's what's trying to boot - possibly because it doesn't like the kernel.img that was created from ocaml-rpi?

Also, I just grepped for "Hello World" in the kernel.img that was generated and it does find the string in there.

---

Reply to this email directly or view it on GitHub:
#3 (comment)

I might have found the problem: I tested a lot on qemu and that loads
the kernel image at 0x10000 instead of 0x8000 like a real RPi. This
ended up in the git repository. So in

https://github.com/mrvn/ocaml-rpi/blob/master/link-arm-eabi.ld

line 26 should read:

. = 0xC0008000;

96725a7

MfG
Goswin

[philtomson]

I tried with your latest update and it does seem to do more than it did previous, but seems to be some kind of exception now:

Uncompressing Linux... done, booting the kernel.
�
Welcome to the rescue system
recovery login:
# uart initialized
_end = 0xC0180000
model = 0xc42 [expected 0xc42]
atags @ 0x00000100
memory size = 0x1c000000
memory_init(0xC0180000, 0x1be80000) : adding chunk 0x1be7ffcc [28]
# stack = 0xC016BFE7
# exception vector set
# enabling IRQs
000000
# doubles tested
strtol("foo", NULL, 0) = 0, errno = 22
strtol("0", NULL, -1) = 0, errno = 22
strtol("0", NULL, 1) = 0, errno = 22
strtol("0", NULL, 37) = 0, errno = 22
strtol("0", NULL, 0) = 0, errno = 0
strtol("0", NULL, 8) = 0, errno = 0
strtol("0", NULL, 16) = 0, errno = 0
strtol("123", NULL, 10) = 123, errno = 0
strtol("20", NULL, 16) = 32, errno = 0
strtol("78", NULL, 8) = 7, errno = 0
strtol("08", NULL, 0) = 0, errno = 0
strtol("0x20", NULL, 0) = 32, errno = 0
strtol("017", NULL, 0) = 15, errno = 0
strtol("0x", NULL, 0) = 0, errno = 0
strtol("+0x20", NULL, 0) = 32, errno = 0
strtol("-0x20", NULL, 0) = -32, errno = 0
strtol("0x81111111", NULL, 16) = 2147483647, errno = 34
strtol("-0x81111111", NULL, 16) = -2147483648, errno = 34
malloc(0x8)
= 0xC0180020 [0xC0180014]
malloc(0x8)
= 0xC0180034 [0xC0180028]
malloc(0x8)
= 0xC0180048 [0xC018003C]
# getenv()
# getenv()
malloc(0x101000)
= 0xC018005C [0xC0180050]
malloc(0x800)
= 0xC0281068 [0xC028105C]
# memset(s = 0xC0281068, c = 0x0, n = 2048)
malloc(0x7d010)
= 0xC0281874 [0xC0281868]
malloc(0x2000)
= 0xC02FE890 [0xC02FE884]
malloc(0x1c)
= 0xC030089C [0xC0300890]
malloc(0x20)
= 0xC03008C4 [0xC03008B8]
# readlink()
malloc(0x20)
= 0xC03008F0 [0xC03008E4]
# getenv()
malloc(0xd)
= 0xC030091C [0xC0300910]
# strcpy(dest=0xC030091C, src=0xC016BFCC)
free(0xC03008F0): @0xC03008E4 0x20 [5]
# __sigsetjmp()
malloc(0x10038)
= 0xC0300938 [0xC030092C]
# lseek64()
# __errno_location()
malloc(0x10038)
= 0xC031097C [0xC0310970]
# lseek64()
# exception_data_abort_handler()
regs @ 0xc017bfc0
R0 = 0xffffffff R1 = 0xffffffff R2 = 0x00000019 R3 = 0x00000000
R4 = 0xc031097c R5 = 0x00000001 R6 = 0xc0065280 R7 = 0xc002256c
R8 = 0xc016bf20 R9 = 0xc006c000 R10 = 0xc0280fb0 R11 = 0xc0181000
R12 = 0xc016add0 SPu = 0xc016bee8 LRu = 0xc0008478 IPu = 0xc0021d84